This invention relates to a method of making the basic material and the facial skin of synthetic leather with one round of process, particularly to one applying one material injecting device to inject foaming plastic on a basic cloth, and another material injecting device injecting non-foaming plastic on a separable paper to form a facial skin, and then the basic cloth and the facial skin tightly combined together to make up synthetic leather when they are in a condition of half reaction and not fully becoming hardened.
Conventionally, to make synthetic leather, a basic material has to be made first. Usually, various materials and solvent are put into one or more saturating tanks, and basic cloth is guided to pass through and be saturated with the materials in the saturating tank, and then the basic cloth is guided into a water tank to let its surface gelatinized and solidified, and finally dried by an electric heat device to make up the basic material of synthetic leather. Further, a facial skin (skin membrane) has to be made, and then the basic material and the facial skin are tightly combined together by means of glue.
However, in making conventional synthetic leather, a large amount of solvent is used whether in making a basic material or a facial skin, possibly resulting in serious environmental pollution. For instance, the solvent used for making conventional moist-mode synthetic leather contains dimethyl formamide (DMF for short), which is easy to cause a person poisoned in case absorbed through skin or breathed in lungs, so it is supervised and restricted in using. According to regulations, the dimethyl formamide can only be used on condition that a factory is provided with devices for collecting poisonous gas, for washing with water and for processing exhaust, and is supervised and recorded by the factory and the government any time, thus taking much time and labor in dealing with the exhaust and waste water, and likely giving rise to serious pollution.
On the other hand, in making conventional dry-mode synthetic leather, a resin spreading way is used, and methyl ethyl ketone (MEK for short) has to be applied for this purpose. But this MEK is liable to cause a person acute hepatitis through breathing in its poisonous gas, and its xylene is high combustible to be ignited by heat, spark or flame, possible to bring forth a fire, and pollute air and water. Besides, the glue used for combination contains solvent, so it is also harmful and dangerous.
In addition, the basic material and the facial akin of conventional synthetic leather are made respectively in two factory premises, and then pressed and combined together by means of glue. And whether the basic material or the facial skin of the conventional synthetic leather has to be made with several rounds of process, and the material for each round of process has to deposited, so a factory premises with a large space is required. Besides, electric-heat drying device is needed for making the basic material and facial skin of conventional synthetic leather, thus wasting too much electricity and labor, and increasing producing cost.
One objective of the invention is to offer a method of making the basic material and the facial skin of synthetic leather with one round of process, using two units of material injecting devices respectively and synchronously to make a basic material with a polyurethane (PU) plastic foam layer and a face-skin layer, which are pressed and combined together, when they are in a condition of half reaction and not fully becoming hardened, saving space for respectively storing materials, shortening a producing process, economizing equipment and labor, and lowering producing cost.
Another objective of the invention is to offer a method of making the basic material and the facial skin of synthetic leather with one round of process, in which the basic material with PU plastic foam layer and the facial skin containing PU plastic ingredient are pressed and combined together during a condition of half reaction and not fully becoming hardened, thus ensuring the stability of their combination.
A third objective of the invention is to offer a method of making the basic material and the facial skin of synthetic leather with one round of process, in which no solvent is used, impossible to cause a fire, and pollute air and water, conforming to environmental protection.
One more objective of the invention is to offer a method of making the basic material and the facial skin of synthetic leather with one round of process, in which reaction-mode PU plastic is used, so the time of its hardening can be controlled according to the amount of the catalyst added in the hardening agent, needless to employ a conventional thermal bellows and possible to economize much electricity.
Still one more objective of the invention is to offer a method of making the basic material and the facial skin of synthetic leather with one round of process, possible to make up preset wrinkled grains of snake skin, hide or suede on the surface of the face-skin layer, enabling the synthetic leather to be used extensively.